Feasibility and synthesis of hybrid reactive distillation systems

A systematic method to synthesize hybrid reactive distillation configurations described here uses three building blocks. These building blocks are a cocurrent rectifying cascade, a cocurrent stripping cascade, and a countercurrent cascade. A feasibility diagram and a product purity diagram provide a global view of the "direct" and "indirect" sharp split products that can be obtained as a function of the reaction rate from single-feed and double-feed hybrid columns, respectively. These diagrams are used as a basis for quickly and systematically generating feasible column configurations (if any) that produce the desired product. Three esterification examples are used to illustrate the method. In spite of the fact that the examples form a homologous series, the feasible designs are quite different. The results compare well with column simulations.